Growing well over 300 feet tall and up to 20 feet in diameter, the coast redwoods have a presence that forces you to recalibrate your idea of plant life. The 10,000 acre Jedediah Smith Redwood State Park has its own Visitor Center, 20 miles of hiking and nature trails, an excellent campground (89 sites, no hookups) and the Smith River, where you can swim, float or just sit quietly and watch the deer as they come down to drink.
If you go:
The campground is open all year round; day use is from sunrise to sunset.
Links:

California State Route 199
Hiouchi, California 95531 USA
Mailing address:
California State Parks
1111 2nd Street
Crescent City, CA 95531 USA
Phone Numbers:
Visitor Center
+1 (707) 458-3496
+1 (707) 458-3496
Entrance Station
+1 (707) 458-3018
+1 (707) 458-3018